Step 1: Understanding the bonding in \( XeO_4 \).
- Xenon has an expanded octet and forms four bonds with oxygen.
- Each oxygen atom forms a \( p\pi - d\pi \) bond with xenon.
Step 2: Confirming the correct answer.
- The molecule is tetrahedral with four \( p\pi - d\pi \) bonds.
CH$_3$–Br $\xrightarrow{\text{CH$_3$OH/Nu}}$ CH$_3$OH
Correct order of rate of this reaction for given nucleophile:

